LHCf Status Report Measurement of Photons and Neutral Pions in the Very Forward Region of LHC Short review of physics topics and detector design Status of the detectors Status of the installation Running scenario Oscar Adriani INFN Sezione di Firenze - Dipartimento di Fisica dell’Università degli Studi di Firenze

The LHCf Collaboration CERN D.Macina, A.L. Perrot USA LBNL Berkeley: W. Turner FRANCE Ecole Politechnique Paris: M. Haguenauer SPAIN IFIC Valencia: A.Fauss, J.Velasco JAPAN: STE Laboratory Nagoya University: Y.Itow, T.Mase, K.Masuda, Y. Matsubara,H.Matsumoto,H.Menjo, Y.Muraki,T.Sako,H. Watanabe Shibaura University Saitama: K.Kasahara Kanagawa University Yokohama: T.Tamura, K.Tanaka Waseda University: Y.Shimizu, S.Torii ITALY Firenze University and INFN: O.Adriani,, L.Bonechi, M.Bongi, G.Castellini, R.D’Alessandro, P.Papini Catania University and INFN: A.Tricomi CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Main problems in High Energy Cosmic Rays (E>1015 eV) Xmax(g/cm2) Energy (eV) Composition Spectrum / GZK Cutoff CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Development of atmospheric showers Simulation of an atmospheric shower due to a 1019 eV proton. The dominant contribution to the energy flux is in the very forward region (  0) In this forward region the highest energy available measurements of p0 cross section were done by UA7 (E=1014 eV, y = 5÷7) The direct measurement of the p production cross section as function of pT is essential to correctly estimate the energy of the primary cosmic rays (LHC: 1017 eV) CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Technical report: September 2005 Letter Of Intent: May 2004 Technical report: September 2005 Technical Design Report: February 2006 LHCC approval: June 7th, 2006 CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

LHCf location in the IP1 of LHC Detector I Tungsten Scintillator Scintillating fibers Detector II Tungsten Scintillator Silicon mstrips INTERACTION POINT IP1 (ATLAS) ~140 m ~140 m Beam line Detectors should measure energy and position of g from p0 decays e.m. calorimeters with position sensitive layers Two independent detectors on both sides of IP1 Redundancy Background rejection CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Installation of the detectors in the TAN absorbers at 140m from IP1 LHCf 96 mm CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Detector #1 Impact point (h) Energy 2 towers ~24 cm long stacked vertically with 5 mm gap Lower:2 cm x 2 cm area Upper: 4 cm x 4 cm area 4 pairs of scintillating fiber layers for tracking purpose (6, 10, 30, 42 r.l.) Absorber 22 tungsten layers 7mm thick  44 X0 (1.6 lI) in total (W: X0 = 3.5mm, RM = 9mm) q < 300 mrad 16 scintillator layers (3 mm thick) Trigger and energy profile measurements Energy CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Detector # 2 We use LHC style electronics and readout 2 towers 24 cm long stacked on their edges and offset from one another Lower:2.5 cm x 2.5 cm Upper: 3.2 cm x 3.2 cm 4 pairs of silicon microstrip layers (6, 12, 30, 42 r.l.) for tracking purpose (X and Y)  impact point q < 400 mrad 16 scintillator layers (3 mm thick) Trigger and energy profile measurements Absorber 22 tungsten layers 7mm thick  44 X0 (1.6 lI) in total (W: X0 = 3.5mm, RM = 9mm) Energy CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Performances of the LHCf Detector Measured at the SPS Beam Test in 2004 SciFi Position Resolution Energy Resolution LHCf can measure (and provide to LHC) the center of neutral flux from the collisions If the center of the neutral flux hits LHCf  << 1 mm resolution CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

p0 mass resolution Dm/m = 5% Arm #1 DE/E=5% 200 mm spatial resolution 2 g identified in the 2 towers Arm #1 DE/E=5% 200 mm spatial resolution Dm/m = 5% CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Monte Carlo g ray energy spectrum (5% Energy resolution is taken into account) 106 generated LHC interactions  1 minute exposure @1029 cm-2s-1 luminosity Discrimination between various models is feasible Quantitative discrimination with the help of a properly defined c2 discriminating variable based on the spectrum shape (see TDR for details) CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Model dependence of neutron energy distribution Original n energy 30% energy resolution CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Summary 1 LHCf can do the proposed physics measurements We will be able to measure π0 mass with 5% resolution. We will be able to distinguish the models by measurements of π0 and γ We will be able to distinguish the models by measurements of n LHCf can provide on-line useful information to machine people (Relative luminosity, beam position, beam-gas rate etc.) CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Where are we with the detectors?

Where we are with Arm1? Arm1 was fully assembled in Japan in July 2006 (scintillators + fibers + Tungsten) and fully tested at CERN in August 2006 beam test CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Where we are with Arm2? Arm2 was partially assembled in Florence in July 2006 and brought to CERN for the Beam Test of August 2006 Arm2 was fully assembled in Florence in April 2007 CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Front Counter (Both for Arm1&2) read by a MAPMT R7600U-00-M4 CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

SPS Beam Test Setup Test was successful CERN : SPS T2 H4 Analysis is under way for Energy calibration of the calorimeters Spatial resolution of the tracking systems CERN : SPS T2 H4 2006 Aug. 28 – Sep. 4 Incident Particles Proton 150,350 GeV/c Electron 100,200 GeV/c Muon 150 GeV/c Setup LHCf Detector Silicon Tracker Moving Table Trigger Scintillator CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

An electron event as seen by Arm1 40mm Calorimeter : 196 GeV electron Transition Curve Scifi e- 2 r.l. step 4 r.l. step 196GeV CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Energy Calibration Problem: Determination of the conversion factor from ADC to Energy in each calorimeter layer ⇒　Ai [ADC counts/MeV] (i: Layer） How to do? Compare data with simulation (EPICS), tuning with beam test data Event Selection (Centered events) 　　Incident point 　　　　20mm 3mm from calorimeter center 　　　　40mm 5mm from calorimeter center 10mm 6mm Beam Profile 　40mm Calorimeter 　196 GeV e- RUN CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Data vs. Simulation Ai = Mean(data) / Mean(simulation) 40mm Calorimeter : 196 GeV 　Red : Simulation 　Black : Experiment Ai = Mean(data) / Mean(simulation) Layer χ2　 D.O.F. 3 42.6 / 60 4 23.8 / 48 5 50.0 / 36 6 64.5 / 38 Simulations and data agrees well!!! Energy scale can be well inferred Work in progress to check the energy scale for different energies CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Few plots of the beam test results for silicon A high energy electron shower seen on x and y silicon X Y <Noise> ~ 5 ADC counts CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Y Energy measured 100 GeV electrons X High Gain CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Summary 2 Both Arm1 and Arm2 have been completed They have been exposed to Beam Test in 2006 They are ready to be installed in the LHC CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Now the real installation in LHC… The idea is that installation takes place in 2 steps: Pre-installation Final installation In between the 2 installation the baking out of the beam pipe will be done (200 oC), so the detectors should be removed Pre-Installation dates have been fixed in Fall 2006 LSS1L (Arm1) 8/01/2007 to 26/01/2007  FINISHED! LSS1R (Arm2) 23/04/2007 to 11/05/2007  will FINISH today The dates for the final installation are still under discussion CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Before pre-installation a long preparatory job has been necessary: Modifications of the TAN Transport machine / Fork lift Cables and fibers from USA15 to tunnel Most of the control electronics and all the power supply system are located in the USA15 Atlas control room > 200 m distance!!! All the necessary cables have been pulled (~100 cables!!!) All the connectors have been mounted All the optical fibers have been installed Electronic racks in USA15 CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Arm1 pre-installation Thanks to all people involved in the installation!!!!! TS/LEA Transport team Cables team Atlas Safety Etc. etc. etc. From 8/01/2007 to 26/01/2007 No major problems came out Cables  OK Transport and installation  OK Laser calibration  OK Power supply from USA15  OK Manipulator and movements  OK Arm1 was dismounted at the end CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Transport and insertion in the TAN CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

LHCf Arm 1 – Installation completed within 15 minutes! CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Arm2 pre-installation From 23/04/2007 to 11/05/2007 No major problems came out Quartz fiber for calibration is damaged  should be replaced Cables  OK Transport and installation  OK Laser calibration  OK locally  TBD from remote Power supply from USA15  OK Manipulator and movements  OK No interference with BRAN Arm2 will be dismounted this afternoon CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Summary 3 A huge work has been done to organize the installation Pre-installation of Arm1 & Arm 2 were succesfull Installation and removal is a ‘fast’ operation! (remote handling is under study) Final installation dates are under discussion CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

The LHCf operation in LHC

Optimal LHCf run conditions Beam parameter Value # of bunches ≤ 43 Bunch separation > 2 msec Crossing angle 0 rad 140 mrad downward Luminosity per bunch < 2 x 1028 cm-2s-1 Luminosity ≤ ~1030 cm-2s-1 Bunch intensity 4x1010 ppb (b*=18 m) 1x1010 ppb (b*= 1 m) Beam parameters used for commissioning are good for LHCf!!! No radiation problem for 10kGy by a “year” operation with this luminosity CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

From R. Bailey presentation at January 2007 TAN workshop Optimal conditions for LHCf running! Stage 1 CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

From R. Bailey presentation at January 2007 TAN workshop CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

LHCf proposed running scenario Phase-I Run since the very beginning of LHC operations (Stage 1, 43 bunches) Remove the detector for radiation issues when the machine goes to the Stage II (luminosity reaches 1031cm-2s-1) and reinstall the 3 Cu bars Phase-II Re-install the detector at the next opportunity of low luminosity run after removal of Cu bars (Totem dedicated runs? Possible LHCf dedicated runs?) Phase-III Future extension for p-A, A-A run with upgraded detectors? We are continously in touch with Machine and ATLAS peoples to agree on detailed running scenario CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

LHCf: conclusions and plans LHCf approved in June 2006 by the LHCC Physics performances: able to measure π0 mass with 5% resolution. able to distinguish the models by measurements of π0 and γ able to distinguish the models by measurements of n Detectors: Arm1 & Arm2 are fully ready Test beam was done in 2006 to measure the performances Installation phase well advanced ARM1 already successfully pre-installed in January 07, ARM2 already successfully pre-installed in April-May 07 Final installation date is under discussion Running conditions: Three foreseen phases Phase I: Run at the beginning of LHC operations (43 bunches) Phase II: operation during low luminosity TOTEM runs or dedicated runs Phase III: Heavy Ion runs ? Waiting for LHC beams!!! CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Back up Slides

Evaluation of Ai 3% ⇒ Ai,196GeV Compare Ai with 196 GeV electron run to Ai with 99.6 GeV electron run. 99.6 GeV/c electron run ⇒ Ai,99.6GeV 196 GeV/c electron run ⇒ Ai,196GeV Ai,99.7 is 3% less than Ai,196 in both calorimeter (Ai,99.7GeV) / (Ai,196GeV) 3% Very Preliminary!!!! CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Epics v.s. Geant4 e- W: 7mm x 16 Scintillator: 3mm 100mm CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report

Y X Beam profile 200 GeV electrons CERN, May 9 2007 - 88th LHCC Meeting LHCf Status Report